Invoice due date calculator
Enter the invoice date and payment terms (Net 15, 30, 45, 60, 90, or custom) to get the due date, counted in your timezone with the invoice date as day 0 and an optional roll-forward when it lands on a weekend or holiday.
Net terms are counted as calendar days, with the invoice date as day 0. Conventions vary, check your contract.
Calculation receipt
- Answer
- Thursday, August 20, 2026
- Operation
invoice_due- Inputs
- invoiceDate: 2026-07-21 · nominal_due: 2026-08-20
- Timezone
- UTC
- Convention
- Whole calendar days, midnight to midnight; today = day 0 (not counted)
- Workweek
- mon-fri
- Holiday calendar
- None
- Valid for
- 2026-07-21 in UTC
- Computed at
- 2026-07-21T03:43:57.397Z
- Versions
- engine 1.0.0 · holiday dataset 2026.07.1
- Result ID
Same inputs, engine, and dataset always reproduce this ID; anyone can verify the answer from the fields above.
How Net terms are counted
"Net 30" means payment is due 30 calendar days after the invoice date, with the invoice date itself as day 0. An invoice dated June 1 on Net 30 terms is due July 1; weekends count like any other day. The same rule scales to Net 15, 45, 60, and 90. That exclusive, calendar-day reading is the standard convention in invoicing, and it's the same counting used across tilwhen, how to count a deadline walks through it with more examples.
Weekend and holiday roll-forward
A due date that lands on a Saturday, Sunday, or public holiday can't always be paid that day, banks don't settle on non-banking days. Many agreements therefore treat the next business day as the effective due date. The calculator's roll-forward option applies exactly that rule, skipping weekends and national public holidays for the country you pick (US federal, UK bank, Canadian federal, or Australian national holidays, including observed and substitute days). If you need to count in business days from the start instead, use the business days calculator, and see counting business days correctly for the method.
Variations to watch for
- Counted from a different day. Some contracts run Net terms from the date the invoice is received or from the end of the month ("Net 30 EOM"), not from the invoice date.
- Business-day terms. A contract that says "30 business days" is asking for a different count entirely, about six calendar weeks rather than one month.
- Early-payment discounts. Terms like "2/10 Net 30" add a discount window: 2% off if paid within 10 days, otherwise the full amount in 30.
Conventions vary by industry and by contract, the wording in your agreement wins. This page explains the common reading; it isn't legal or accounting advice.
How we calculate
- Counts whole calendar days, midnight to midnight, in your local timezone.
- Counting is exclusive: today is day 0 and is not counted.
- Business days are Monday–Friday by default (other working weeks are selectable where offered). The holiday-aware result skips public holidays only for the holiday calendar you choose in the calculator: United States, United Kingdom (England & Wales, Scotland, or Northern Ireland), Canada, Australia, Uganda, or your own custom list. There is no default calendar; each result names the one used and lists the excluded days.
- No login and no server: every result is computed in your browser, so you can verify it yourself.
Sources
- Federal Holidays, U.S. Office of Personnel Management
- UK bank holidays (England & Wales, Scotland, Northern Ireland), GOV.UK
- Public holidays, Government of Canada
- Public holidays, Fair Work Ombudsman (Australia)
- ISO 8601, date and time format, ISO
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